The present invention relates to a method of writing data on an optical record carrier such as a CD-R (compact disk recordable), a CD-RW (compact disk rewritable), a MO-disk (magneto-optical disk), and the like.
In a state-of-art record carrier, such as CD-R, CD-RW or MO disk, a wobbled pregroove is typically provided for marking ATIP (absolute time in pregroove) codes. The ATIP codes provide a basis for the data recording apparatus to read or write information on the record carrier. The prior arts regarding the wobbled pregroove and ATIP codes may be found in the U.S. Pat. No. 5,226,027 and xe2x80x9cOrange Bookxe2x80x9d, 3rd edition, published by Philip corp. in 1997.
However, based on the prior arts, writing error and interruption still occur during writing of data on the record carrier. So a portion of or entire record carrier cannot be read due to the writing errors. The major possible reasons for the unsuccessful recording of data on the storage unit of record carrier include the defects, scratches and stains which are not detected prior to the writing of data.
These reasons are described summarily as follows. (1) Wrong ATLP codes with inconsistent CIRC checksum are marked on the record carrier. (2) Format not complying with the standard format specified in xe2x80x9cOrange Bookxe2x80x9d. (3) Scratches are accidentally made over the substrate of the record carrier after the manufacture of the record carrier. (4) The finger print, dust and stains imposed over the record carrier after the manufacture of the record carrier. (5) The scratches are made over the reflective layer of the record carrier after the manufacture of the record carrier.
Aforesaid defects of (1), (2) affect the quality of the record carrier significantly and defect in (2) mainly results from the issues of material and procedure control during the manufacturing. The defects due to the reason (2) can not be easily detected by the reflected signal from the surface of record carrier. However, by detecting error occurred in reading ATIP codes, the detection of the defects of (1) and (2) can be accomplished easily. Moreover, the detection of ATIP codes can be implemented by using the current information record system. Therefore, detecting of ATIP codes can be used as index indicative of the quality of record carrier.
The defects of (3), (4) and (5) can be detected by the reflected signal from the surface of the record carrier.
Accordingly, an objective of the present invention is to provide a method of write data over an optical record carrier employing the pregroove and ATIP code. The invention is to successfully detect the storage units, on the record carrier, on which data can not be written. Furthermore, the storage units, on which data can not be written due to defects, scratches and stains, are labeled as unrecordable.
Another objective of the invention is to provide a reliable write method of data over an optical record carrier without changing the configuration of an information recording apparatus. The invention is implemented by detecting the error occurring in reading ATIP codes and the reflected signal from the surface of the record carrier.
According to a first preferred embodiment of the invention, a method is provided for writing data on a storage unit of a record carrier having a pregroove on which a predetermined ATIP codes are marked. A predetermined sets of number-ranges are defined. Each set of number-range corresponds to a write speed and a write power used to write data on the storage unit. The method includes the steps of:
(1) reading the pregroove ATIP codes from the servo track of the storage unit;
(2) generating an error-count by analyzing the decoded ATIP codes from the corresponding storage unit;
(3) determining whether the error-count obtained falls within one set of number-range; and
(31) if No in step (3), labeling the storage unit as unrecordable;
(32) if YES in step (3), writing data on the-storage unit based on the write speed and the write power corresponding to the one set of number-range.
The error-count of the decoded ATIP is the accumulated number of occurrences of either one of the following errors: (a) the CIRC checksum of the decoded ATIP code is error, but can be corrected; (b) the CIRC checksum of the decoded ATIP code is error, and can not be corrected; and (c) the min/sec/frame time value is not continued between two consecutive storage units.